Finite groups | Multiplication | Modular arithmetic

Multiplicative group of integers modulo n

In modular arithmetic, the integers coprime (relatively prime) to n from the set of n non-negative integers form a group under multiplication modulo n, called the multiplicative group of integers modulo n. Equivalently, the elements of this group can be thought of as the congruence classes, also known as residues modulo n, that are coprime to n.Hence another name is the group of primitive residue classes modulo n.In the theory of rings, a branch of abstract algebra, it is described as the group of units of the ring of integers modulo n. Here units refers to elements with a multiplicative inverse, which, in this ring, are exactly those coprime to n. This quotient group, usually denoted , is fundamental in number theory. It is used in cryptography, integer factorization, and primality testing. It is an abelian, finite group whose order is given by Euler's totient function: For prime n the group is cyclic and in general the structure is easy to describe, though even for prime n no general formula for finding generators is known. (Wikipedia).

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Integers modulo n

The integers modulo n under addition is a group. What are the integers mod n, though? In this video I take you step-by-step through the development of the integers mod 4 as an example. It is really easy to do and to understand.

From playlist Abstract algebra

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The Additive Group of Integers Modulo n

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys The Additive Group of Integers Modulo n

From playlist Abstract Algebra

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Abstract Algebra | Group of Units modulo n

We sketch a proof that the equivalence classes of integers which are relatively prime to n form a group. This group is called the group of units modulo n. http://www.michael-penn.net

From playlist Abstract Algebra

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Theory of numbers: Multiplicative functions

This lecture is part of an online undergraduate course on the theory of numbers. Multiplicative functions are functions such that f(mn)=f(m)f(n) whenever m and n are coprime. We discuss some examples, such as the number of divisors, the sum of the divisors, and Euler's totient function.

From playlist Theory of numbers

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Jean-Marie de Koninck: On the proximity of additive and multiplicative functions

Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b

From playlist Number Theory

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Multiplicative order of a congruence class

In this video we introduce the concept of multiplicative order and we prove several properties and go over some examples. The content of this video corresponds to Section 8.1 of my book "Number Theory and Geometry" which you can find here: https://alozano.clas.uconn.edu/number-theory-and-

From playlist Number Theory and Geometry

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Introduction to the Modulo Operator: a mod b with a positive

This video introduces a mod b when both a and b are positive. mathispower4u.com

From playlist Additional Topics: Generating Functions and Intro to Number Theory (Discrete Math)

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Number Theory | Inverses modulo n

We give a characterization of numbers which are invertible modulo n.

From playlist Modular Arithmetic and Linear Congruences

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Introduction to number theory lecture 30. Fields in number theory

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We extend some of the results we proved about the integers mod p to more general fields.

From playlist Introduction to number theory (Berkeley Math 115)

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Introduction to Number Theory

Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in

From playlist Computer - Cryptography and Network Security

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Elliptic Curves - Lecture 11 - The Tate module

This video is part of a graduate course on elliptic curves that I taught at UConn in Spring 2021. The course is an introduction to the theory of elliptic curves. More information about the course can be found at the course website: https://alozano.clas.uconn.edu/math5020-elliptic-curves/

From playlist An Introduction to the Arithmetic of Elliptic Curves

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Introduction to number theory lecture 27. Groups and number theory

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We show how many of the theorems of number theory are special cases of theorems of groups t

From playlist Introduction to number theory (Berkeley Math 115)

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Example of Group: GL(2, R) (3 of 3)

Abstract Algebra: Let G=GL(2, R) be the group of real invertible 2x2 matrices. We consider two group actions for the group GL(2, R) on itself. We interpret the results in terms of linear algebra and change of basis. We also explain how conjugacy classes of G relate to the diagonalizati

From playlist Abstract Algebra

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Introduction to number theory lecture 29. Rings in number theory

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We show how to write several results in number theory, such as the Chines remainder theorem

From playlist Introduction to number theory (Berkeley Math 115)

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Introduction to number theory lecture 28. Products of groups

This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We define products of groups, and rephrase some earlier results in terms of these products.

From playlist Introduction to number theory (Berkeley Math 115)

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Primality Testing

Cryptography and Network Security by Prof. D. Mukhopadhyay, Department of Computer Science and Engineering, IIT Kharagpur. For more details on NPTEL visit http://nptel.iitm.ac.in

From playlist Computer - Cryptography and Network Security

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Group theory 17: Finite abelian groups

This lecture is part of a mathematics course on group theory. It shows that every finitely generated abelian group is a sum of cyclic groups. Correction: At 9:22 the generators should be g, h+ng not g, g+nh

From playlist Group theory

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A Short Course in Algebra and Number Theory - Fields

To supplement a course taught at The University of Queensland's School of Mathematics and Physics I present a very brief summary of algebra and number theory for those students who need to quickly refresh that material or fill in some gaps in their understanding. This is the third lectur

From playlist A Short Course in Algebra and Number Theory

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Definition of a Ring and Examples of Rings

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Definition of a Ring and Examples of Rings - Definition of a Ring. - Definition of a commutative ring and a ring with identity. - Examples of Rings include: Z, Q, R, C under regular addition and multiplication The Ring of all n x

From playlist Abstract Algebra

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Multiplicative Subgroup of a Field is Cyclic

We prove an initially unintuitive fact about subgroups under multiplication of fields. To do so, we prove a classic result that polynomials of degree n have at most n roots.

From playlist Abstract Algebra

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Quotient ring | Disquisitiones Arithmeticae | Integer factorization | Chinese remainder theorem | Klein four-group | Primitive root modulo n | Ideal (ring theory) | Group (mathematics) | Torsion subgroup | Carl Friedrich Gauss | Greatest common divisor | Trivial group | Euler's totient function | Group isomorphism | Generating set of a group | Quotient group | Cryptography | Finite group | Primality test | Direct product of groups | Carmichael number | Quadratic reciprocity | Gauss sum | Modular arithmetic | Integer | Product of rings | Cyclic group | Ring (mathematics) | Number theory | Least common multiple | Abstract algebra | P-adic number | Carmichael function | Abelian group | Modular multiplicative inverse